org.openimaj.math.util

Class RunningStat

java.lang.Object

org.openimaj.math.util.RunningStat

public class RunningStat
extends Object

This class is used for providing a running mean and variance of streams of data. Use the push(double) method to add data from the stream.

Version:

$Author$, $Revision$, $Date$

Author:

John Cook (http://www.johndcook.com/), Converted to Java by David Dupplaw (dpd@ecs.soton.ac.uk)

See Also:

"http://www.johndcook.com/standard_deviation.html"

Constructor Summary

Constructors

Constructor and Description
RunningStat() Default constructor
RunningStat(double firstValue) Constructor that takes the first value

Method Summary

Methods

Modifier and Type	Method and Description
void	clear() Reset the running stats
double	mean() Returns the running mean.
int	numDataValues() Returns the number of data values that have been processed.
void	push(double x) Push a data value from the stream into the calculation.
double	standardDeviation() Returns the running standard deviation
double	variance() Returns the running variance

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RunningStat

public RunningStat()

Default constructor

RunningStat

public RunningStat(double firstValue)

Constructor that takes the first value

Parameters:

firstValue - the first value in the stream

Method Detail

clear

public void clear()

Reset the running stats

push

public void push(double x)

Push a data value from the stream into the calculation.

Parameters:

x - The data value to push

numDataValues

public int numDataValues()

Returns the number of data values that have been processed.

Returns:

the number of data values that have been processed.

mean

public double mean()

Returns the running mean.

Returns:

The running mean

variance

public double variance()

Returns the running variance

Returns:

the running variance

standardDeviation

public double standardDeviation()

Returns the running standard deviation

Returns:

The running standard deviation